In a Flash
by Lovingh3art
Summary: In the breathtaking third part of the "Potluck" series, a Chaos Emerald winds up in Central City. Unfortunate circumstances send the Flash to the world of its' origin, causing him to run into Sonic the Hedgehog. As friends of both try to remedy the situation, a third party with nefarious intentions takes advantage of it all.
1. The Impossible

**A/N: After a lot of one-shots and short stories, I'm back on the "Potluck" train. For anybody who doesn't know, this is the third act in an anthology series of crossovers, originating from my first fanfic "Potluck" and then it's spiritual successor, "Darknight Universe." Now it's time for the third time, and this case involves a rash of symptoms such as the Flash and Sonic the Hedgehog! Before we enjoy, though, here's the disclaimer...**

 **Disclaimer: I do not own The Flash or Sonic the Hedgehog. Any locations, characters vehicles, and other quirks are directly from shows and video games created and owned by DC Comics, WB Television, and SEGA.**

* * *

Chapter One

 _The Impossible_

If anybody had ever run fast in his or her lifetime, they might've felt the urge to scream at least once. Sometimes it was a thrill ride and others a massive shock. But what really made it unique was how free you were. When you ran, there was no biases, no problems, and no distractions. There was only you and your destination, guided by your eyes and greeted by the wind.

For Barry Allen, that was easier said than done. Running was what defined him, and for good reason; he happened to be the Flash, after all. When he wasn't rushing through Central City to fight metahumans or avert the end of the world, he would rather be with those he loved. Getting to see Iris, chill with his S.T.A.R. Labs buddies, and even scoring the occasional coffee from Jitters meant running. Every time he did it, lightning coursed and wind splayed across him in a couple of sped-up seconds. He loved it.

But even running wasn't enough for his psyche to digest. In the handful of years he'd been the Flash, Barry had encountered many foes worth his mettle. The worst of these were fellow speedsters that could spar equally with him. Each time he thought one had been defeated, another rose to take their place, almost like a speed force Hydra. Now he was dealing with the Thinker, a literal brainiac who could outthink him in apparently everything. However, was that really any better than what he thought he'd gotten out of?

He couldn't do that. He had to believe in himself and keep going, one day at a time. If he let the doubt sink in and spread, he'd be right back like he was in the past. Quick, mistaken, and lashing out at others. So for the sake of himself and those he cared about, the fastest man alive had to literally slow down.

* * *

Iris' eyes fluttered awake for a brief second before she fully awoke from her slumber. Lifting her head up, she realized that Barry was not in their bed and must've gone out. Getting her slippers on, she walked around for a bit prior to realizing that he had been busily cooking in the kitchen section of their apartment. As she stalked closer to his backside, she saw a glimpse of what appeared to be eggs and pancakes sizzling on the griddles.

"Breakfast? You shouldn't have."

Barry whipped around and gave her his trademark smile. "It's nothing," he said cheerfully. "I had some extra time on my hands, so I thought I'd do something special."

"Like every morning? You don't have to, you know," Iris smirked as she sat down on the other side of the island, her fingers gripping a small glass of orange juice already prepared. "Just because you're the Flash doesn't mean you have to spend all your sped-up time doing everything."

"Okay, okay," he said while humorously holding his hands up in a sort of defense. "What do you think of the juice?"

Deciding it was best to oblige to his request, Iris drank the orange juice and put the glass down while digesting it. A patient Barry waiting, she licked her lips and breathed in relief. "…Pretty good," she replied in a satisfied comment.

"See? Being married to the fastest man alive has orange juice benefits."

"Don't push your luck, Barr," replied Iris sarcastically. Both smiled before she ran into his arms and immediately kissed him. As they continued to do so, everything else felt like it just froze into place around their action.

* * *

Later that day at S.T.A.R. Labs, the rest of Team Flash was gathered around the cortex and found themselves at a complete loss for words. Despite getting Barry out of jail, Devoe was still ten steps ahead of them, and they'd just lost another Bus Meta in the process. At this point, hopelessness and personal doubt seemed to have been shaken into everyone's brains, and it was clearly infringing upon a breakthrough of any kind.

Cisco leaned back in the chair behind the main computer console, yet another drink sitting mere inches away in his hand. Caitlyn and Ralph were against the nearby wall, the former thinking of some potential weapons and the other bored out of his elastic mind. The only other person who was there and actually doing something happened to be Harry. A pen in his hand, signs of his annoyance were evident on he scribbled marker upon the clear erase board. Whatever he was attempting to draw was anybody's guess at this point, helped in no part by his stubbornness and lack of communication.

"Harry?" Cisco asked, a tint of concern evident. "Earth to Harry Wells. What are you working on?"

The genius' face didn't even turn as he continued to scribble. "Leave me alone, Ramone."

"You sure you don't need a chill pill, Harry?" Ralph asked out of nowhere. "Because there's this drugstore on 7th and Infantino that's pretty great for stress meds. Tried it myself a couple times."

"While I would love to hear that story if I weren't a genius, " Harry said while turning around (and making sure to emphasize 'genius'), "I can't. Devoe is still out there, and we are lagging miles behind him. We're children to whatever he's planning, and even with - with all this - we've got nothing! Gaagghhh!" He had half the urge to chuck his dry erase marker at the lot of them but refrained from doing so in the first place.

Ralph shrugged. "Geez, talk about a party pooper," he muttered under this breath.

"Ralph…" started Caitlyn. "Just…give him a break, okay? We're all under a lot of stress."

"You can say that again," Ralph said before realizing something and smiling like it was his birthday. "Oh, wait, you can! You know, you and your other half…Get it?"

Nobody smiled or laughed in response.

"Dude?" Cisco deadpanned. "I've made better bad jokes than that. Get some original material."

Wherever the conversation might've gone next was immediately interrupted as Barry and Iris strolled into the corridor holding hands.

"Hey guys," Iris said cheerfully. "How's it going? Anything interesting happen?"

"Interesting? Bah!" Cisco lamented. "If, by interesting, you mean Harry hogging the board and acting like he's the king of this place, then yeah, that counts."

"I am not hogging the board, Ramon," Harry iterated in a cynical tone. He put down the marker before turning to see the newcomers. "I'm simply doing my best, using my not-hyper intelligence, to try my hand at deducing Devoe's next move.

"Aren't we all?" Barry asked. "Y'know, I'm starting to think we need a break from this."

"You mean like a vacation?" Caitlyn perked up at his suggestion, almost like she'd been waiting to say it. "I hear the Bahamas are great this time of year."

"For Killer Frost, maybe," said Ralph. "Hardcore yoga work for anybody? Or…ooh! Another try at the Golden Booty? Huh, huh?"

Cisco shot him a questionable look. "Ralph, I thought you swore off going there after the fight we started."

"What can I say? Old habits tend to stretch out their welcome."

"I don't remember that being the saying," Barry interjected, "but sorry, both of those are not what I was talking about. We" - he said while gripping Iris' hand even more tenderly - "thought we should do a good team-building exercise. Go out into the city…see a movie, maybe? Like what everyone we save does on a good afternoon."

Caitlyn shrugged in a semi-complacent display. "That…sounds nice? I guess it could work."

"Awesome!" Iris responded. "Cisco? Ralph? Harry?"

"If there's a Big Belly Burger included in the end of this trip, count me in," Cisco replied nonchalantly.

Harry almost didn't register the idea. "I'm sorry, Allen, but I'm going to have to pass."

"Oh, come on, Wells!" Ralph remarked. "If we're all going, you've got to come!"

"And why would I do that?" Harry asked him.

"Because, man, peer pressure! Right?"

Barry mentally facepalmed at Ralph's attempt to make a joke. "I don't think Harry really buckles to peer pressure, Ralph."

Harry was about to respond, only to be interrupted by the arrival of a black man in dark clothing and carrying a badge and gun on his person; Detective Joe West, Iris' father and Barry's surrogate for one. He looked downright alarmed, which was becoming something of a statement regarding his job these days.

"Guys, we've got a problem…" Joe said in an urgent manner.

"What's wrong, Joe?" Caitlyn asked.

"Turn on the news," he stated flatly. In response, Cisco lazily grabbed the remote and flicked it on. The televisions around the cortex sprung to life, showing a live news report of what appeared to be a massive fire down in the heart of the city. Everyone's eyes paid close attention to the caption: "MASSIVE FIRE BREAKS OUT IN HEART OF CENTRAL CITY; DISASTER OR METAHUMAN ATTACK?"

"That doesn't look too good," Ralph said, evidently shocked at the sight.

"Understatement of the year," added Harry, "but yes, that fire does pose quite a problem."

Barry looked at Cisco. "Do we know anybody who can cause fires? Because I'm coming up with blanks."

"Well, Firestorm's officially caput," Cisco said as he counted off with his fingers, "and him being a bad guy seems…not right? Then there's Rory, but he's with the Legends, so I think he's off our watchlist. Beyond that, my knowledge is comparable with yours; zero."

"Why don't we spend less time theorizing and more time stopping this?" Iris demanded. The outburst caused everyone to focus their attention on her. "Come on, people; the city's counting on us to put this fire out!"

"Right!" Barry exclaimed. A couple of seconds passed and the familiar rush of air breezed through the cortex, blowing hair and sending papers flying. The lightning that was her husband came to a standstill and revealed him, decked out in the familiar red suit he was so famous for using. "Race you guys there?" He poised with a smirk.

"Hold your horses, Speedy Gonzales," Cisco demanded, putting on his Vibe gear as quickly as he could. "Not all of us happen to be as fast as you are when it comes to changing clothes."

"Eh. You'd be surprised." To the gaping of a few, Ralph had already gotten into his costume and was standing triumphantly, looking smugly at the others.

"How - never mind," Caitlyn said. "Somebody piss me off!"

"Oh - okay," Joe responded as best he could. "Uh…what was that name again?"

"Lexie LaRoche!" Iris screamed at her. The result was a chilling transformation, watched by everyone as the sweet Caitlyn seemed to melt into the shape of a darker persona. Her hair turned white, her eyes and lips swirled blue, and cold air burst from her fingertips. Killer Frost had arrived, and she looked as twisted and awesome as ever. At least, before she gazed down at her outfit and stared open-mouthed.

"Seriously? Why does Caitlyn like wearing pink shirts and blue jeans? I prefer leather."

"I can help with that." Frost was swept up in Barry's familiar lightning for a few seconds. She came out of the temporary vortex complete in her dark-aqua get-up, as well as the ice buckle on her belt.

"You got everything I needed," she said sweetly," but next time, ask first."

Barry's attempted retort was interrupted by an irritated Harry. "Uh, hello? Burning park! You need to go!"

Barry nodded his head, turned and bolted away in a flash of yellow. Killer Frost and Ralph both looked to Cisco, who blinked his eyes and scrunched his hands together. On cue, one of the many breaches he could manifest at will appeared in front of the trio. "Welcome to the Ramon express," he said light-heartedly. "Step aboard if you desire!"

* * *

In a place very far from what people associated with existence and reality, something made itself known. A small green glimmer almost drowned in the blackness surrounding it, shined off and on until the pressure from the outside was unbearable. With the willpower of a million stars, the energy inside rattled to battle the darkness, sending it away as it continued to fight against the barriers put around it. With enough pressure, they cracked, piece by piece, until eventually they fell apart and let the object fall through into the unknown.

A worrisome figure reached his hand out for the item, but by then it was too late. It had fallen into the abyss…and he had no idea where it'd gone.

* * *

After running for what amounted to around thirty seconds, Barry came to a grinding halt. His panting was cut off, though, when his eyes gazed up at the devastated Hearthstone Park, whole sections of it burned. Benches and pieces of concrete were lit ablaze by a seemingly alive fire. Out of the corners of his eyesight, the scarlet speedster saw clusters of citizens running or screaming as the blazes came closer. Just how had this happened, and where was the fire department?

To the Flash's relief, he whirled around in time to witness his three allies arrive on the scene, ejected from their breach. "Wow," Cisco said as he looked over the destruction. "That really is hot. Maybe I should've worn less leather."

"No problem for me," Frost interjected. "I'm as cool as an icicle."

"And they say I make bad puns," mumbled a Ralph

"Guys, that fire is spreading across the whole park," Iris said urgently from the com links, rousing them all to focus. "We've got to stop it and help everyone out of there at the same time."

"What's your plan, boss?" asked Cisco.

"Cisco, I'm putting you and Ralph on crowd control. Get everyone away from that fire. The fewer civilians in trouble, the better. Frost, I need you to contain the fire. Stave it off as much as you can, or at least drown the smaller ones. Anything goes."

"Hang on a sec," Killer Frost breathed. "Exactly what is lightning here going to do?"

"He's going to put out the fire," Iris said over the com-link hurriedly. "Everyone set? Good. Now let's roll!"

Barry took once deep breath in and rushed with all his might into the flames, his lightning drowned out by the intense heat. Frost wasn't far behind him, already shooting freezing blasts of cold air at the inferno. Vibe and Elongated Man were the only two left, and that left them taken aback at just how hectic the situation was.

"Ralph," jibed Cisco as he took off towards the corner. "Come on, man!"

"Coming!" Like an aroused child, Ralph went off after his partner. "Give me a head-ups next time, will ya?"

"I'd love to chat, but we're in the middle of a FIRE here!" Vibe stopped abruptly when he saw a family several feet away, huddled in the midst of a sea of fire from all sides. When Ralph came to join him, he gripped his shoulder. "I've got an idea."

"What's that?"

"I'll vibe you over there, and all you've got to do is stretch them to safety. See? Heads-up."

Ralph shrugged. "Whatever works." As Cisco opened yet another breach, he jumped headfirst and found himself rocketing towards the ground, right over the family. Just as he was about to collide with them, his legs instantaneously stretched and supported him upright. Shocked at the newfound appendages next to them, the family looked up at their new savior. Elongated Man smiled before stretching down his hands. "Hey, folks! I'm here to get you out of here! Who wants first?"

* * *

Another small blaze was drowned into submission by Frost, already having worked her way through some trees and newsstands. Most of the fire was gone, but a large flame had rested near the central fountain and was encroaching itself on some near shrubs. The pure size and intensity of the heat sent shivers down her spine. Just what had made this happen?

The Flash stopped beside her, wincing from running so fast. "I tried taking some of the bigger fires out, but this one just won't go…"

"Same for me," Frost lamented. "It's too far gone at this point."

"You tried freezing it?"

Frost glared at him. "You don't think I did that already? The fire's eating away at what I throw at it." She turned back to release a small gust of chilly air to keep away the flames, which was all she could do at this point. "What about running around it? Didn't that work for you before?"

"I would, but there's no counting how many people I'd suffocate taking the oxygen out of play," he replied frantically. "And that's not even considering the blowback from something this hot. There's got to be another way."

"Well, you might want to go with extinguishing the giant birthday candle." The two were taken by surprise when Ralph and Cisco showed up. Both showed signs of being hot and exhausted, but still had the energy left to act.

"Guys, what's up with the fire?" Asked a frantic Iris from over the line.

Barry put a gloved hand to his comm. "Iris, the fire's too large. I try to extinguish it, the resulting blast might hurt the entire area."

"Well, we've got to do something!" Ralph pointed out. "I don't want my last moments on earth to be being melted to a crisp!"

"Wait, what did you say?" Cisco asked him.

"Uh - that I don't want to be melted to a crisp?"

Cisco face lit up in joy at the comment. "Ralph, you're a genius!" He turned back to the others and brought his hands out in separate motions. "Frost, Flash, I've got a crazy idea."

Taking one look at the flames close to surrounding the four of them, Frost shrugged. "I'd scoff, but considering our options, I'll listen."

"Okay, here's the plan," Cisco remarked to the three of them. "Barry, I want you to run around the fire to put it out."

"But I-"

"I know, I know!" Cisco said impatiently. "But while you're doing that, I'll vibe Frost and me up over the fire to add in some cold air. You run fast enough, the cold air will be spread around so quickly, it'll force the fire to die!"

The scarlet speedster smiled. "Good plan!"

"Only one way to prove it, though," Frost pointed out. "Hopefully doesn't involve the dying part."

"Don't worry," said Elongated Man. "You guys can do this!" He held his thumbs up in support.

Barry turned back and gazed at the now searing conflagration. His heart paused, his fists clenched, and he ran so fast that everything devolved into lines and fleeting glimpses of color. He ducked and jumped over everything in his path until he established a pattern, running around the blazes repeatedly. He could feel the air beginning to fold into itself, but he didn't know for how long it would take.

To his relief, a faint pop was heard amidst the sped-up repetition badgering his ears. Keeping his path in his line of sight, he quickly glanced up to see Cisco and Killer Frost falling from a breach at least twenty stories above his position. Too focused on starving the fire, he made out a series of shouts and shrill yells before a decreased temperature flooded everywhere. He felt it seep into his fabric, which was enough to let him know that the plan was working. But he still had work to do.

He pushed, he screamed, and he propelled himself faster than he'd gone recently; the magnificent result was a groan from the fire, the heat going down and the size shrinking while smoke replaced there once-lit flames. After one last run, he vaulted over a far-off railing and planted his feet at the close tree. Steadying himself, the fastest man alive turned back to glance upon the extinct fire. Billowing amounts of smoke and shared pieces of the park could be seen everywhere, but Barry knew in his mind that the worst had passed them by. The park was safe.

"Flash!" He swerved to the left, overjoyed at seeing his three compatriots okay. As they got closer, he gave them all a smile.

"Thank god you're all okay," Barry said. "Crazy plan that was. What were you guys saying, exactly?"

Frost shot Cisco a cynical glare. "I told him he'd put us too low over the fire. He's lucky I made an ice bridge to get us out of there."

"Hey, hey!" Cisco replied defensively. "It worked, didn't it? The best people take risks now and then."

"Eh," Ralph chimed in. "I'd say it was too close."

"Thank you," the ice queen complimented.

The commlinks sparkled back to life with Iris' voice. "Hey, you guys okay? The readings Harry cooked up say the fire's caput."

"Yeah, we're fine," Barry relayed back to her. "Cait-I mean, Killer Frost and I put our powers together and snuffed it out."

"All right…well, that's good news…" Iris trailed off.

"Allen!" Harry's voice was now on the comms, though it was clear that the four heroes hadn't expected his vocals to scream into their ears. "Did you find anything indicating who caused the fire?"

"Uh…not yet, Harry," Cisco answered. "We should probably start looking."

"Guys?" The trio looked back to Ralph, an elongated arm pointing to the distance. "What about that?" His fingers gestured towards strewn pieces of something metal and robotic. No other options present, they darted to the discarded remains a good distance away. When they arrived at the spot, they looked the scene over. It appeared to be pieces of some kind of robot; wires, shoulder pads, and apparent wrist guards the color of orange were on top of the charred grass.

"What…isn't this a robot?" Ralph questioned.

Vibe swatted down, his hands combing the parts for something to find. Immediately, his fingers connected with something. "…I think I might've figured out what happened."

"What?" Barry asked.

His friend's hands circled the ground until it reached a chunk of large, orange armor with a dent the size of a football in the middle. "Look at this. The grass is scorched black. What's left of the armor must've been strong enough to survive, but everything else…decimated beyond repair."

Frost narrowed her eyes. "What are you suggesting?"

"I think that the fire must have originated from this robot. I mean, it's not like a crazy idea to build a fire-starting bomb and then put it in a robot. Lots of movies do it."

Ralph looked around. "Who'd want to build something like this? I know this city has its crazies, but jeez…"

"And apparently, that's not the only gift we've gotten today," Killer Frost remarked coyly. To answer their impending questions, she got up and turned to them. Shocking the other heroes in the gathering, her palm held a hefty green emerald with thinly cut edges and an almost inhuman aura beaming from it. It shone a brighter green, then backed down to its normal color.

"Guys?" Iris asked. "What's going on?"

* * *

 **The end of chapter one! This story is only just beginning, and many more twists, turns, and explanations for what's happening are soon to come. Heck, Sonic and friends are bound to show up soon! Please favorite or review, even a simple read is good for this tale. To next time, all!**


	2. Never Vibe a Chaos Emerald

**First, I just want to say thank you to everyone who's read this, reviewed this, and favorited this. This story is only beginning, and I'm excited to start this journey with you. in fact, here are some responses to some reviews...**

 **Shian1998: Thank you! The idea of them being in "Potluck" coming back in this in some way...maybe!**

 **DoctorWhatTheHeck41: Thank you very much! It's fine that you skipped "Darknight Universe." In fact, if you think about it, this being an anthology series of crossovers is like something such as "American Horror Story;" you can read the ones you want and skip the ones you don't like or don't know. And trust me, this is going to be one you'll like!**

 **So anyways, let's start the chapter!**

* * *

Chapter Two

 _Never Vibe a Chaos Emerald_

* * *

Morning swept over the large valley, covered with trees and jagged rock structures all around, at a riveting pace. Soon, the sunlight had rushed up a tall, marble-colored structure and made its way to the top. Directly in the middle of said structure's peak was a towering crown jewel; a literal diamond the size of a car, green in color and extremely radiant. It was so voluptuous in sight, some might've felt compelled to take it for themselves. Luckily, there was one thing standing in the way of that.

The guardian in question stood in front of it, solitary and with his red arms folded. Roughly four feet tall, Knuckles the Echidna had red skin, spiky hair and two spiked fists that looked like they were itching to rip through something. This particular morning was the same for him as any other; he breathed, huffed, and guarded the Master Emerald with his very life. Anyone who would do it harm or steal it for evil means would face his wrath.

Yet there was a sudden glow from the emerald itself. It took some seconds for him to register the radiance permeating on his back. When he caught onto the brightness, the echidna gasped and darted right up to its' green surface. Putting his gloved hands on the jewel, he closed his eyes in an attempt to discern what it was blinking about.

"Master Emerald…what are you trying to tell me?" He asked slowly.

The Emerald glowed brighter, sending a myriad of images into his head. People in spandex ran off, just as or faster than Sonic. Wait…that didn't make sense. But as his thoughts became jumbled, that got to be a repeated cliché in of itself. Buildings like City Square with people and odd eggs in the middle. Explosions. Robots built by…Eggman? And to cap it off, he foresaw a horrifying sight; a defeated hero laying on the ground, dea-

Knuckles broke from the concentration and looked upwards, sweating from his vision. He shook it off and darted down the steps, panic flooding his mind. He had to tell someone about it.

* * *

For some reason she couldn't hope to explain, Iris was unusually worried for Barry today. The last time she'd been this frantic was when her husband disappeared into the Speed Force for six months. This incident wasn't necessarily as big or dangerous; in fact, it was just the same kind of danger he normally faced on missions. And yet, her gut wouldn't sit right until she was certain it was over.

"Harry," she barked in an unintentionally loud voice, "You hear from the team yet?"

The arrogant Earth-2 scientist rolled his eyes. "I'd like to annunciate that the chatter cut out right when they found something, Iris…But knowing Allen, I'd say it's nothing to worry about.

Not believing in anything, Iris folded her arms. Joe noticed her reluctance and moved to give her some comfort. "Iris, Barry and the others…they've been through worse. They'll be fine."

"I-I know, dad," she replied back, "but I…I'm just worried today for him…I wish I knew why…"

Her ears betrayed the sudden churning behind her, and Iris wheeled around to see a breach parked in front of the entrance to the Cortex. Out of the indigo-colored portal came the four heroes, slightly dusty and disheveled but looking all the better. Once it closed, she soon came to find that their happy-go demeanor has grown sour.

"Barry!" She ran to her husband, ironically not quick enough to respond before she embraced him in a hug. "Are you okay?"

"'Course I am," he replied with a quickly-woven smile. "Why wouldn't I be?"

Iris blushed, backing up a little as she regained herself. "…Yeah, right. Sorry. Just worried a bit."

Cisco scrunched his eyes while taking off his goggles. "Besides surviving an inferno, I really need to vent this suit out. It was just sweltering being out there."

"Then maybe you shouldn't wear so much leather, Ramon," Harry commented.

"Ok, Harry- "

"Hey!" Killer Frost shouted to everyone, getting their attention with both the interruption and an annoyed face. "I don't know about you all, but I've had enough of holding…whatever the heck this is." The green emerald held by her very fingertips, she placed it on the top of the central computer station. "There. Now you can geek out over it."

Joe held a disbelieving gaze while walking closer to the jewel. "That's what caused the fire? This day just gets stranger and stranger."

"Not exactly…" Barry cut him off. "We found the remains of a robot from the blast site where the fire occurred. My guess? Based on the scorch marks and debris metal, somebody deliberately planted a bomb inside so it could explode."

Ralph put a spandex hand up to his chin in thought. "You know, there's always that Trickster guy. What if he planted the bomb?"

"Yeah…wouldn't fit his M.O," Cisco pointed out, all the while circling around to see the emerald for himself. "He's always about clowns and color, not robots."

"Forget the robot," Harry demanded. "What about this emerald? It was, what, just laying around?"

Cisco looked back to Barry and Frost, who shrugged their shoulders, and then to Harry. "Uh…yeah. It kinda' was."

Unconvinced, the scientist laid a finger unto the green jewel, contemplating something. "It's a common scientific fact that emeralds don't have a high density towards being damaged. For one to survive an explosion of this magnitude, not to mention a fire…there's something wrong with it."

"Then let's figure out what's up," Iris stated, snatching the emerald and walking over to the scanners in one of the two smaller rooms on the sides of the Cortex. Just as the others caught up with her, she slid it underneath the station and turned on the machine. Already, results had begun to pile up on a couple of closely-knit computer screens. "Uh…so what do these mean?"

Harry pushed himself past her to get a look at the results, though something seemed wrong on his face. "They're saying…this emerald is absorbing and channeling energy into itself, like some sort of battery. And currently, it's holding…more than enough to power an entire city."

"An entire city?" Ralph's face contorted into a look of skepticism once he heard the information. "This gem sure gives 'mad with power' a new meaning."

"Here's what I don't get." Joe said to the scientists. "So, the bomb was in the robot. That's clear. But someone put an emerald next to the blast zone; an emerald, which, by the way" – he pointed back to the green jewel in the midst of his rant – "can suck energy into itself. And we just happened to find it?"

All Barry could do was give him a humorless smirk. "That's what we know, Joe."

* * *

Station Square was a unique place. It wasn't New York City, but it was a bustling metropolis filled to the brim with street vendors, garbage, and rampant crime. People could walk a few blocks and find something excitingly dangerous in their midst. So, if, say, a blue hedgehog sped through town looking for chili dogs, pedestrians treated it as the norm.

Sonic the Hedgehog was in a positive mood today. It was normal for his schtick to be upbeat, but after running along the lake and taking some time to work out, his stomach was growling for something to eat. Then he remembered the Chili Dog Stand on Griffith Ave and bolted to it. The closer he got, the more he imagined his lips munching on a chili dog.

Eventually, he stopped with a small dust cloud on his feet. The hedgehog hero walked up to the food stand, noticing a blue wolf behind the counter. At his entrance, the wolf looked up while gripping his notepad. "Hi, what can I get you?" he asked.

"Well, I think a regular chili dog will do," Sonic said. He dug out a crisp $5 from his pocket and gave it to the cook. "That covers it, right?"

"Sure thing," the wolf breathed back, heading to the back of the food truck with the money in hand. As sounds of grease and food being cooked filled his ears, Sonic turned around to gaze at the rest of the park. It was meant to get him to be patient, but the view was still lovely. He tried dispelling the sounds of fried onions and meat long enough to focus on what he'd planned on doing today. Yet he only drew up blanks, as he hadn't thought that far ahead.

Then his ears picked up on some kind of wind vibration, only to realize it was a sign of someone he knew. A yellow fox with two tails landed next to him, gloved hands and a positive smirk on his face. "Hello there, Sonic," he the fox greeted politely. "Getting a chili dog?"

"You read my mind," Sonic replied back. "Say, you wouldn't happen to have something for that…would you?"

Tails shook his head. At least it was a try. "Not yet. Though there are some things I've been working on lately- "

"Sir?" The wolf at the food stand stood up, a chili dog in his paw wrapped in tin foil. Seeing that his food was complete, Sonic skipped over and gleefully received it. The wolf tipped his hat, giving them a "Have a good day" as they walked off.

The blue-quilled hero opened the chili dog, sniffing the familiar smell and smiling. He took a bite out of his before crunching down. "Dis good stoof," he garbled through bites.

"So, any plans today?" Tails asked, looking around Station Square to find it surprisingly empty. He surmised it must've' been early in the morning for most residents in the area.

"Nooo…" replied Sonic, continuing to chew the Chili Dog, but managing to swallow to talk. "Things've been pretty quiet, especially from Eggman. And I already got a run in this morning, so I'm kind of just chilling."

"Sonic…" Tails grew serious. "If Eggman's not doing anything…maybe he's working on something in the shadows?"

"Eh. Tails, I wouldn't worry," Sonic made a point with. "We've got all this time to relax. Why not- "

"SONIC!"

The two heroes stopped in their tracks. Knuckles the Echidna was bolting straight towards them, angrier than ever and with a dust storm right behind him. To their luck, he went to a halt just before their position and took several breaths in, puffing his chest out to breath. "I…I need your help."

"We figured, Knuckles," Sonic pointed out. "Yelling my name kind of spells it out."

"No, you don't…understand." Knuckles said, standing up. "The Master Emerald…it warned me of something."

"The Master Emerald?" Tails was definitely embroiled in the conversation now. "What'd it tell you?"

"One of the Chaos Emeralds is missing," the echidna deadpanned.

Sonic and Tails' jaws dropped. "That's impossible," the hedgehog retorted. "We divided the emeralds up among us three and the others. Whoever got it stolen from would've pinged us by now…right?"

"It wasn't just any emerald, Sonic," responded Knuckles. "It was yours."

Sonic's face ran white, a look he rarely used only in the direst of situations. "We should check my place…now!" He turned and immediately dashed off, his form degenerating into a poignant blue line. "Meet you there!"

"Wait up, Sonic!" Tails had already begun flying after him, leaving Knuckles to follow in their wake as fast as he could keep up. Passing buildings, intersections, and tons of establishments spread around, they eventually came upon a small green house located on the outskirts of the city. Knuckles ran immediately up to the door, already cracked open, and unlocked it further to get inside. Tails followed up, but by then Sonic was already in his living room, and the seriousness hadn't left him at all.

"My emerald…it's gone," he declared seriously.

"How?" Tails pondered, confounded as well. "How could this had happened?"

"More importantly," said Knuckles, "where?"

* * *

The conversation between the heroes at S.T.A.R. Labs was getting nowhere. Harry was still baffled by the incomplete results regarding the emerald, Ralph was being unhelpful, and Joe felt more in the dark than ever. The unproductive session was just about to make Iris' brain pop from the lack of progress…until she got an idea.

"What if we've been looking at this all wrong?" That got the attention of the squabbling scientist.

"What exactly do you mean?" Harry questioned.

"Lab results…they could go either way at this point," Iris stated. "But we do happen to have a more reliable and human way of figuring this thing out…" Slyly, one of her fingers jabbed towards Cisco, though the hint was obvious to him at this point.

"You want me to vibe it? Sure. It'll be easy," he said confidently, walking over to the emerald.

"Just be careful, Cisco," Barry warned. "We don't know if this thing is safe or not."

"C'mon," Cisco said sarcastically. "It's not like this thing is a nuclear bomb." His hands gripped the jewel in a grand motion, then his eyes shut and he attempted to concentrate. The rest of the heroes exchanged looks, somewhat concerned at Cisco's transfixed position and small bits of mumbled dialogue. The motion went on for so long, Barry thought maybe he should end it all. But right when he was about to pull the plug, Cisco screamed. Some kind of force shot him back, slamming into one of the walls and dropping the emerald onto the floor in panic. Caitlyn, who by this time had melted back from her Killer Frost persona, ran over to help her friend.

"Cisco!" She cried in worry. "What's wrong?"

"I-I…it was too much," Cisco cried out, his dialogue stuttered by the paleness on his face. "It was all this random stuff…and then it just overloaded me!" It was then that his eyes enlarged, and Cisco pointed right back at the emerald in horror. "What's happening?"

Barry and Iris, along with the others, turned to gaze at the gem. Where it once had been a green jewel that glittered once or twice, some sort of power now had taken hold over it, and it wasn't letting go. Crackling sparks sizzling over, the green lighting up to yellow and red and every color in the spectrum. Caitlyn put a hand to her mouth in shock at the sight.

"That emeralds become radioactive!" Harry shouted. "Vibing it must've done something to the energy inside!"

"Radioactive?" Ralph replied. "We've got to get this thing out of here – no, out of the city!"

"What if we just breach it?" Joe suggested, looking to help somehow.

"Won't…work," Cisco garbled, trying to get up despite being in a shock.

"He's right," Caitlyn added. "Putting something that volatile through the breach to the multiverse…there's no telling how many earths its' energy could spread to!"

"Then what others options are there? Because that emerald sure isn't getting cooler!" Ralph shouted. True to his word, the emerald had now shone an even lighter color, but with more powerful energy coming from it. "Boss? What do we do?" He asked Iris.

The reporter puts her hands together and tried to think, yet every plan she'd tried before was caput at this point. The pressure, the people depending on her, the volatile gem in their midst…it was all too much, and she couldn't think properly. Why couldn't she just-

"I'll do it." The words of stone, cool power emanated from the mouth of her husband, already suited up and with his mask over his head. Iris' dread returned when she looked to him.

"Barry, no!"

"Iris, this emerald…someone's got to get it to a secluded area!"

"But what about you?" Iris demanded. "I just got you back…again! I don't want to lose you…"

"Allen!" Harry had gripped the gem in one hand, though it was evident from his face that he couldn't hold it much longer. "This emerald is going to go supernova is less than twenty seconds!"

In the brief moment, Barry looked at his wife and smiled. She didn't have any time at all before he gripped her and embraced her in a passionate kiss. And then, equally as fast, he'd snatched the emerald and made off with it into his lightning. Iris screamed his name, just standing there as she realized how much emptier it was without him. Everything seemed to lose sound, but she still saw the rest of the team, shocked or hectic, looking at the tracker on Barry's suit as it sped away. Farther and farther it went from the city, picking up speed and heading towards the Badlands. Just as he had reached the point, a pink shape enveloped his signal and a loud noise seemed to flood through the entire city. Immediately following this, the screen cut to black.

Tears lining her face, Iris collapsed to the floor, sobbing. The rest of Team Flash faded from her line of sight, what with her surroundings only being darkness.

He was gone. Again…

* * *

 **Well, that was pretty dark...but things do get better. Until a week or so, fellow readers!**


	3. Whole New World

**A/N: Back with a vengeance, this chapter is! Very pleased by the reviews, Shian1998 and DoctorWhatTheHeck41, and the following. I'm going to try to make each chapter push this story forwards so it feels more complete. And trust, the ending of this chapter is super important. Always, feel free to review, favorite, or just take a peek. This is for you guys! And here's some answers...**

 **Shian1998: Thank you! I worked Knuckles' visions in this story very much like those of Garnet in Darknight Universe; a slice of what may and may not happen. To find out what events do occur, you'll have to continue reading. As for Sonic and co, they make their big collision with Barry this chapter.**

 **DoctorWhatTheHeck41: Thank you! That's my intention, to make a relatively good pace and keep things fresh as well.**

 **Now, onto the story!**

* * *

Chapter Three

 _Whole New World_

* * *

When he was younger, Barry had thought about death. He'd wondered if his mother was either in heaven, hell, or really just decayed by worms in her casket. The cold, undying aspects of the final resting place seemed more interesting than him living a life. But even as he got older, he couldn't shake the feeling. Death was everywhere; in his family, his friends. And if it wasn't them, it was most definitely in his casework.

The faster he got to the badlands, all Barry could think about…was this it? Was he going to go out like this, just after getting his freedom back and returning to normalcy?

Apparently not.

As he felt the energy begin to pick away at himself, the scarlet speedster glimpsed a blinding translucent glow emanate all around him. Suddenly, cold and hard pressure tucked his body into some sort of bind. He couldn't see, couldn't feel anything except a dark rush. He wanted to get out of it…and he was, the light fading to leave him be. Coughing, he looked up at his surroundings. Thick, tall buildings made of silver surrounded him in vast height, and the gleam was blinding in spots. He was…home?

Barry suddenly remembered he had the emerald in his palm and looked at it. Whereas once it had been about to blow, the jewel was as inactive as it normally should've been. He sighed, praising whatever had deactivated it…though he was still curious. He got up and took a step in his surroundings, still unfamiliar with this section of Central City. Deciding it was would be best to return to S.T.A.R. Labs and reunite with his friends, he took off.

Faster he went around ordinary streets packed with people, but nothing seemed to jog his memory. There were at least a dozen or so buildings and establishments he'd never seen before. A massive skyscraper was planted in the center of the space he was running around, the letters "G.U.N" printed large and bold. The speedster slowed down to catch his breath, planning on continuing down the street until he found a landmark he recognized. Then he stopped dead and his eyes crept slowly to the left.

There was a pink bird…walking on the sidewalk. In clothing.

Barry blinked his eyes several times to make sure he wasn't hung up from whatever had happened, but the animal was still moving into the distance. His jaw dropped. Was she a meta? How were people just taking it as normal and continuing their business? …Were there more around?

He slowly cocked his head around…and sure enough, there were more. A dog made conversation with a woman in a coffee shop a block down. Two hyenas jogged their way uptown. It was like being in a kind of Disney fantasy. Luckily, it took him a second or two to remind himself that walking, talking animals wouldn't have been the weirdest thing he'd seen.

Shaking his head, the Flash turned back towards the rest of the city and made a break for it. Iris and the rest of his friends had to be waiting for him. And if he got further lost, then maybe he'd ask somebody for directions.

 _There have to be,_ he thought. _At least something._

* * *

To say that Team Flash was unhappy would be a mistake of an understatement. At the moment, Iris couldn't help but cry and sit in the same chair, feeling as if darkness has caught her in its hold. She wanted him back…but he was gone. Even he couldn't survive an explosion. Just thinking about it was emotionally suffocating.

Ralph walked over to her, his hands in his pockets and his face dour. "Iris…" he trailed off sullenly. "…I'm sorry for…what happened…"

She looked up at him tear-faced. "What?"

"It…it was my fault," he elaborated. "I was the one who found the emerald at the park. And…I thought it could help, but…Allen's gone, and- "

"Ralph, no." Iris' words rang through the entire space, a kind of thick directive in them. "What happened to Barry…it's not your fault. Nobody here is at fault…" It was so hard for Iris to speak through her tears, but she managed anyways. "The only thing that's to blame…is that stupid emerald!" After that, she ducked down and put her head in her hands. A sympathetic Caitlyn walked next to her and patted her shoulder, giving Ralph the chance to just stand there to bare the sobs.

"Ramon. West. A moment," Harry said to the other two.

Joe looked offended. "Are you serious, Wells? We just lost- "

"Now." He wasn't joking at all in the way he said it. Cisco took the hint and followed him back to the hallway, Joe behind him but appearing perturbed. Once they were against the bending wall on the other side of the cortex, Harry checked to see if they were alone. Then he took a deep breath. "Allen isn't gone. And before you criticize me for saying so, just listen."

Cisco folded his arms. Joe coughed and clenched a fist, another in his pocket defensively. "Go on," he breathed.

Readjusting his glasses, Harry continued. "When Allen went out to the badlands, I saw a momentary blip on the screens before they all went black. It was a cyan blip. Ring a bell?"

"Uh…no," Joe said, lost.

Harry sighed, but made sure not to make it obvious how what he was insinuating was child's play. "Do you know what energy is cyan on a scan, Ramon?" He asked Cisco. "Tachyon particles. And those tachyon particles appeared out of nowhere right when the explosion occurred."

"Wait a sec…" interrupted Joe. He looked like he was on the verge of a breakthrough. "Tachyon particles…those are the things you leave when you time travel, right?"

"Exactly," Harry said. "Or, as we've experienced in the past….travel to another world."

Cisco's jaw dropped, then he immediately closed it. "But…every time someone's gone to another world…there's been at least a breach. Wouldn't the satellite detect traces of one?"

"Not always, Ramon. Breaches themselves are tears into the multiverse generated by truly unfathomable power. With the amount in that emerald…it must've acted the same way."

"And you think Barry's there?" Joe asked, hope filling his eyes. "You think he's not dead?"

"Yes, I do." Harry gulped, almost as if to go back on his own statement. "First, though, we'll need to find traces of the particles in the badlands. Which is much better than moping around here."

Cisco breathed in a sigh of relief. Then he ducked back to the Cortex and shouted, "Yo, Dibny!"

Contrary to what Cisco expected, Ralph hurriedly walked to the trio instead of stretching. "What is it, Cisco?"

Joe talked first. "There's a chance…Barry might be alive."

"What?" Ralph responded. "No wa- "

"There's no time," Harry interrupted blatantly. "We're going to prove it right now, like it or not. Planning on coming with us?"

Ralph gazed over them and thought on it for a bit. Then he looked up. "If it means Rookie's okay…then yeah. I'm in."

* * *

Sonic's feet lifted off the ground as he ducked and ran over a small crop of green hills. Tired as he was, he couldn't stop until he found a trail leading to the emerald. That's why he was searching for it intently, dashing around the outskirts of Station Square with ease. Tails had combed the skyline and Knuckles was canvasing another route. Unfortunately, no results yet, but that didn't kill their determination.

He circled back to the highest hill looking down at the city and stopped, hoping to admire the view before he went back at it again. All the little dots and figures filtered into his mind. Trees, cars, animals like him and people behaving normally.

Then something changed. His eyes caught onto a yellow-red dash, careening through the city blocks in a haphazard fashion. He swore he saw lightning, and that was enough to convince him to get on the chase. Sonic galloped a few steps and immediately took off, dashing downhill and straight through the wilds. In a matter of seconds, he was back in Station Square, and no sooner had the very blur he was looking for sped past him. He scurried behind it. The faster he went, the quicker the person or thing he was chasing seemed to be. They turned corners and dodged over cars. The wind was being picked up, but they were so enthralled they weren't paying attention to it.

Things came to a head when the hazel distortion ran up the side of a building, leaving a linear line of lightning behind it. Almost immediately Sonic was catching up, but he made sure to avoid the sparks in his opponent's wake. Focusing on that cost him time, what with his target getting closer to the top. Almost out of options, Sonic realized something and dug into his pocket. He pulled out a small golden ring, clutching it tighter as the air from speeding ahead clawed at him.

"Hope this works!" He shouted, then immediately applied pressure to the ring. A powerful burst of yellow sucked him in and spat him out. Just as the lightning would've reached the top, the familiar blue blur went past him and skidded to a stop on the expansive roof. The sudden move sent the lightning into a crashing motion, collapsing heavily nearby.

Feeling the effects of the power ring fade away, Sonic got himself a good look at the mysterious speedster. He was a human dressed in dark-red spandex with patches of yellow draped across his boots and arms. His face was hidden behind a well-constructed mask, but he didn't look too happy expression-wise.

And then he saw what was in his hand.

The _Chaos Emerald._

Sonic tensed. The stranger in red noticed this and chose to tense as well. "…I get this is kind of out of nowhere and all, especially since I don't talk to hedgehogs much, but…I'm kind of lost."

"Really? Zipping around Station Square? Or was that before you nabbed my Chaos Emerald?" Sonic blanked.

The speedster gazed at the emerald in his palm, then gawked. "That's what this thing is called? A Chaos Emerald? Must be worth the trouble it caused."

"…You stole that without knowing what it was?" Sonic was confused.

"Wait a second!" The figure said defensively. "I didn't steal this, and I really don't know where I am! Can you just calm down for a sec and be rational in all this?"

Taking a moment to consider what he'd said, the hedgehog hero decided to agree. "…Fine. What's your name?"

"The Flash," the man said passionately. He walked forwards and held out a hand. Sonic eventually took it cautiously. "I take it this is yours?"

Sonic grinned. "You're very perceptive, Flash. The name's Sonic. Sonic the Hedgehog."

"Nice to meet you," the Flash stated. He held out the jewel to the hedgehog hopefully. "Here. You can have it back."

The whole affair was surprising to Sonic. Out of nowhere, he could have his emerald back? It seemed too good to be true, but then again…he didn't want to jinx it. He eagerly reached for the emerald, cupping it in his hand. Despite being satisfied, however, he didn't like the aura he that he was feeling.

"Thanks," he replied cheerfully. "So, you said you're lost?"

The speedster chuckled awkwardly. "It's a long story…but yeah. You good at directions?"

"Just as good at running, too," Sonic said. "I've got a friend of mine who could probably help ya.' Race you there!" Then he whirled around and darted down the side of the building, emerald in hand. The Flash just stood there, shocked.

"And I thought I was the impossible…" he muttered in a bemused way. Collecting himself into a stance, he took off after his new friend with positive energy.

* * *

The badlands were a section of Central City's countryside left to waste after a small radioactive spill. Much of the plant and animal life was gone, and all that remained were small vestiges of dirt buried by heavy piles of sand and ash. Whenever things might've gotten nuclear in Central City, the badlands acted as a good testing ground.

The breach opened in the midst of the area, spewing Cisco, Harry, Joe, and Ralph out. Accustoming themselves to the barren wasteland of an environment, the four walked quickly to the epicenter of a large black hole in the ground. Wells took out a scanner from his pocket and immediately fawned over the sand with it.

"Anywhere, in particular, we should be looking?" Joe asked, his eyes trained on the massive splash of blast marks they were in.

"Try and find the epicenter of the blast," Harry said, focused on his meter. "That's where tachyon particles are most likely to congregate."

Ralph nodded and turned to the other direction, gazing directly at the scorch marks permeating his line of sight. A few feet in the direction and his eyes widened. "How's this for an epicenter? Cisco? Harry?"

Cisco walked up to him, almost about to deny his findings when he let his jaw hang. The very spot Ralph has located bore the darkest blast marks of the entire area. More shocking was the sparkling bits of energy floating mere centimeters over the spot. "He's right! We found some particles!"

They made way for Harry and Joe, the former inching closer and scanning it with his device. Immediately, the meter scorched up to a blazing red. Harry froze dead and looked back at the sizzling grains of sand now levitating above the blast mark.

"What's it say?" Ralph wondered out loud.

Harry looked back and sighed. "The good news…is that these particles are definitely Tachyon particles. Something, most definitely Allen, was propelled through a wormhole to another plane of existence. And the fact that they're still sizzling means it wasn't too long ago."

"Phew," Cisco breathed in relief. "That's good to hear."

Joe, however, was still unconvinced. "What's the bad news?"

The earth-2 scientist got up to glare daggers at them. "You want to know? If this data is correct…Allen may have been sent somewhere beyond our multiverse."

* * *

From a shadowy lair, a large man with round glasses and an explosive mustache watched several screens in front of him. One was completely static, another showed recorded footage, and a third watched over Station Square. He was enjoying soaking up the information, but frankly, it had become boring at this point.

"Master?" Eggman looked behind his chair, finding the shape-based Orbot and Cubot looking at him with urgency.

"What? What is it, you pesky fools? Is there something new you have for me, or are you going to waste my time?"

The two shivered with fear, looked at each other, and strolled forwards. Orbot was the one to speak. "You requested data on the Chaos Emerald anomaly, correct?"

"…Yes. Why?"

The tiny robot flexed his hand. "I-I mean, the two of us, recently discovered footage of that emerald reappearing in Station Square. And you will most definitely be surprised as to what it picked up."

Eggman's face contorted into a menacing glace, his mustache large and looming as his fingers interlocked. This most definitely has his attention. "Do tell, Cubot. Do tell…"

* * *

 **That's all for now, folks. Though I can promise next time things get only more complicated for Barry and his new blue blur of a friend, as well as for Team Flash back on Earth-1! See you then!**


	4. Running to Get Home

**A/N: Thank you all very much for the support and love! School's kicking in like usual, but I'm planning on continuing this and some other stuff regularly. Thank you very much to BateShot39 and Fleetlord Avatar for following and favoriting this, and the reviews were spectacular. Speaking of which...**

 **Shian1998: Thank you! Sonic and Barry's friendship is definitely going to be explored here. As for Eggman, he'll reappear soon...**

 **Fleetlord Avatar: Thank you very much! I'm glad you're enjoying this, especially as your Zootopia/Flash crossover was excellent writing. That robot theory will be addressed soon. As for a race? Consider that a running gag for now (no pun intended!)**

 **So without further ado, chapter four!**

* * *

Chapter Four

 _Running to Get Home_

* * *

Two colorful presences, one blue and one crimson, darted to the front porch of a secluded laboratory located on the edge of the city. Sonic was first, his quills flexing as he steadied himself, and right next to him stopped his new ally, the Flash. He panted while looking up at the house they were gazing at.

"Your friend…he lives here?" Barry asked curiously.

Sonic shrugged. "Yep. Tails likes the peace and quiet, but then again, he isn't a smart fox for nothing. The concentration helps with his work."

"Trust me, I understand," the scarlet speedster commented as they walked up the steps. "My best friend's a tech genius who also moonlights as a pop culture dictionary."

"Really?" Sonic looked amused. "Do you get most of his references?"

Barry laughed. "Most of the time. But it's nice to have somebody you can just chill with." The hedgehog nodded and opened the door, Barry following him inside. He saw that the lab was a good-sized space filled with a worktable island, racks of equipment, computer monitors, and a refrigerator. As he neared the latter, he saw that a photo of Sonic and a yellow fox was plastered onto the surface by magnets. The image made him smile at how happy they were.

His attention was pulled away by a loud CLUNK! In the distance. He looked back, as did Sonic, when the same yellow fox from the photograph emerged. He was scrawny but soft-furred, with blue eyes and the exact same gloves Sonic was wearing. Then he noticed the two tails emanating from behind him, making him all the more curious.

"Oh, hello…" Tails stuttered at the two of them. "Sonic, I wasn't expecting you back so soon…with a friend?" His expression locked onto Barry, puzzled by the masked man and the specific design of his outfit.

"Tails, meet the Flash," Sonic pointed out. "He's the lucky guy who found – actually, had – the Chaos Emerald we were looking for." To prove his point, Sonic produced the jewel out of his hand and twirled it around a bit.

"Wha-wow!" The fox rushed over to his friend, accidentally knocking a couple of loose tools over in the process. "That's amazing…but how'd-sorry, I mean…you're called the Flash?" He asked, looking over the new arrival, who held his hand out in a friendly gesture.

"The one and only," he replied politely. "Nice to meet you." Tails took his hand and shook it heavily.

"But why's that your name?"

Before answering, he looked to the discarded items. "Just watch." In a splash of incredible light and energy, he shot around the room. Tails could only gaze and be transfixed by his lightning, whereas Sonic leaned against a table. When he stopped in front of the fox again, the room was much neater than it had been a few seconds earlier. "That's why."

Tails' eyes enlarged. "You're fast…" he breathed. "Maybe…just as fast as Sonic?"

The two speedsters exchanged looks, then laughed dryly at the idea.

"Eh…I wouldn't push it right now…" Barry pointed out. "Though I'm not against a friendly race."

"Me neither," Sonic lamented, "but we've got way bigger fish to fry. Like the Chaos Emerald, for instance."

Tails looked to the emerald and then to the superhero in their midst. "All right…I think I get that you're a speedster. And from the looks of it, probably not from around here. But how did you get your hands on Sonic's emerald?"

"Honestly? It's a lot to explain…" he trailed off and then shrugged, "…but considering my circumstances, I might as well tell you." He moved back and sat on the nearest worktable, then cupped his hands together and looked down. "What have you guys heard about alternate universes?"

* * *

"Outside our multiverse?" Iris asked disbelievingly. "Is that even possible?"

Harry massaged the bridge of his nose; elaborating on science today was really starting to tire him out. "I'm not saying it's the exact truth, but my readings didn't detect a breach. And, if my word is somehow not enough, Ramon…" he gestured to the junior scientist, perking up at his mention.

"Right back to what he said, Iris," Cisco added. "I couldn't get a lock on where Barry is from those particles. Earth-15, Earth-2, even Earth-X…nada."

Ralph's brow fluttered and then lifted, an idea in his mind. "Wait a minute…Allen's powers come from that Speed Force stuff, right? Why not build a doohickey or something and track him with that?"

Caitlyn sighed. "We'd need more than particles to track him, Ralph. Then you'd have to take into account all the different speedsters in the multiverse, and the- "

"We get it, we get it!" Joe exclaimed frenetically. He stared down at the monitor, sighing with his fists planted even on it. "Seems like whatever we try is going to end up a loose end."

Nervously, the rest of the group didn't speak, the silence almost sickening. But then, Iris breathed in and whirled around, determination coursing through herself.

"Dad, no. We can't give up." Her chest heaved as she continued. "Barry's been lost before…stuck in the Speed Force, alternate dimensions…Heck, he fought an emo version of himself that came from the future. And we've found him again and again. We. Did. Because he's our family and the heart of this team. So there has to be a way. I know there is."

Caitlyn shifted in her spot, gripping her arm with the other hand. "Iris, don't think for a second that none of us want to find him," she mentioned. "He's helped us all in our own ways…but this kind of math and science is beyond what we normally deal with."

"Actually…" Everyone looked to Cisco, nervously on the brink of spilling something. "There might be someone who has better experiences with dimensional travel…that could help us."

Harry didn't act fazed at the mention. "Are you talking about whom I think you're talking about?"

Cisco smiled. "Trust me, she's the best at this. I mean, other than me."

* * *

Tails poured a cup of coffee for himself and drank it, but even something that sugary had no effect on his mind. Not after the mind-blowing revelations he'd heard from the Flash.

He'd gone on for minutes and then an hour, rambling about many things the two of them never considered before. Apparently, multiple universes with small or massive differences existed, separated by the unique frequencies they vibrated at. From what the human speedster had told them, making powerful enough energy was the best way to cross over dimensions. And thanks to his running, he'd done this time and again – though he mentioned that a good portion of the worlds he went to weren't the best.

Then he went into his origin. His own mother being murdered, his father thrown into jail, and then the lightning years later…Tails' might've said it was a sped-up tale, but that'd be getting too literal. As Barry (yes, that was his name, spilling it after pulling his mask down to reveal a human face) mentioned, he'd fought metahumans with the power of science fiction and other super-athletes with the mindsets of gods.

He and Sonic were humbled. Their exploits had saved the Earth time and again, even taking on mystical and alien foes far greater than Eggman. But the yarn he was spinning seemed to be on another level entirely.

When he'd finished, the blue hedgehog blinked his eyes twice and breathed in. "Crazy…so you fight crime as a superhero?"

"Yeah," Barry confirmed, "though that's not my whole life. I'm a forensic scientist for my city's police department, so I'm examining crime scenes when I'm not running around."

Tails perked up at the revelation. "Gee. It seems handy being a scientist and a superhero in one, right?"

"Sure…" Barry scratched the back of his neck and looked down. "It's a lot more dangerous than it looks, though. Having this kind of power…it makes you see weird stuff sometimes."

"Try me," Sonic challenged lightheartedly. "I've been a werewolf and taken down a corrupt king Arthur."

The human snorted. "Uh, well besides fighting speedsters with god complexes for three years in a row, I've never gotten my hands on a nuclear emerald before, let alone one that sent me to a parallel universe." He looked back to it, lying neatly on a far-off counter. "Just what exactly is that, anyway?"

"Glad you asked," Sonic quipped as he scooted off and nabbed the emerald in his palm. "It's called a Chaos Emerald. There's seven of them, and each one contains stuff called Chaos Energy. With one, you could power a machine or get stronger. Collect all seven? You'd be near-invulnerable."

"What, they can just give you ultimate power? Barry answered.

"In a way," explained Tails. "Finding them is the tricky part because everyone seems to always be fighting over them. Half the time, they're getting lost across the planet.

"That's why Eggman's always trying to nab them from us," Sonic added. "He either wants them to build new machines or take over the world." He smiled mischievously. "Maybe they're the reason his ego's so inflated."

Barry's brows sunk into confusion. "Another thing. Who's this Eggman guy you're talking about? He sounds like an egomaniac."

Sonic chuckled, leaning against a table parallel to Barry's position. "That's because he is. He's this brilliant inventor with a crazy IQ, but he considers himself better than everyone else. So he builds massive, destructive robots to constantly wreak havoc.

"You could say he and Sonic have a rampant rivalry," said Tails. "He's always plotting to take over the world, but Sonic stops him every time."

Barry prepared to react, then paused and thought on his words. "You know, that sounds a lot like the guy I'm facing right now back on my world. He's called the Thinker. He's this metahuman with an amazing intellect, but it's killing him, so he's finding and taking over the bodies of other metas."

"That sounds sick," Tails replied.

"It is," Barry continued, "but what's worse is that I don't know what his endgame is. For the moment, he's been quiet. And I can't help wondering if he's started hurting people again…Just when I'm off somewhere else…"

Sonic saw the worry in his face and straightened up seriously. "Then let's help you get back, okay? It's the least me and Tails could do. Right, bud?"

The fox collected himself into a positive stance, walking to stand next to his friend. "Yeah! I'll do my best."

Barry's gaze lightened up again as he stood up. "Thanks. Where do we start?"

"Right…" Tails put a finger to his chin. "Maybe if we want to figure out what's wrong with the Emerald, we should do some physical testing."

"Like a short jog?" Sonic poised.

"Not necessarily," concluded tails. "I think it'd be better if we recreated the position you were in that brought you here."

Sonic looked to Barry. "I guess it's time for a tag-team jog."

* * *

The park was located at the tip of Central City, flowers blooming and birds flying around. Yet the fire and subsequent explosion earlier seemed to cast a dour mood over it, and nobody could be seen walking in it. Then a breach opened up and spat Cisco out onto the pavement. He collected himself and looked down the park path, seeing nobody in the vicinity.

"You sure picked the right spot, Cisco," a warm voice floated down the back of his neck. A swirl later and the familiar eyes he adored were there. "No people, calm atmosphere. Just the right place for a meetup." Her warm smile was temporarily hidden behind a flowing curl of black locks.

He put on a smile. "Good to see you, Cynthia. Really, I'm so happy we get to see each other outside of your job."

"Me too, amante," she vocalized softly. "Where else in the Multiverse am I supposed to get coffee?"

He chuckled slowly.

"But that's not why you called…is it?" Her eyes shone a quick glare at him, signifying that the gig was up.

"Points to figuring it out." The happiness shrank from his face as he paused. "My friend, Barry? He's gone."

Grief washed over her, building to a slow response. "Oh, Cisco, I'm so- "

"No, no!" He exclaimed. "Not that kind of gone. He's not dead, we know that, just lost somewhere. But we don't know where."

The look of grief on her face was instantly replaced by skepticism. "This has happened before, right? Just check the other earths."

"That's the thing…" Cisco trailed off steadily. "He had this emerald with some crazy energy in it when he disappeared, and the particles that he left at the site of his disappearance don't match up. I mean, they don't lead me to any one of the fifty-three earths."

Her eyes froze. "Cisco…what color did this emerald shine when it went off?"

"Green. Why?"

"You're not dealing with a gem. You're dealing with a Chaos Emerald."

* * *

The Flash and Sonic stopped just short of the city's edge, arriving at a large patch of barren wilderness. Mostly manila sands, there were few pieces of nature you could see inside. Sonic gazed up and down the spot before looking back to his new acquaintance.

"All right, this is the place. You ready?" He asked.

The scarlet speedster nodded, noticeably concerned about something. "Think so. It's just kind of déjà vu – dealing with this all. It looks a lot where I was when I – you know – disappeared."

Sonic grimaced slightly, giving him an arm pat. "Don't worry. I'll be keeping up with you and making sure this all works out. You're gonna' be fine."

Barry nodded heavily. "Okay. Here goes nothing…" He held his hands out and pulled them back. When the lightning coursed into his vision, he was off and left a blast mark in his starting spot. Sonic bolted right after him to keep up.

Scurrying at a rapid pace through the vast environment, he felt his speed picking up. The wind chocked and tore at his costume, and the recent events were clouding his mind. But, remembering Iris, everything cleared, and he kept going forwards. He looked back at Sonic briefly, slowly catching up but still a short distance behind his acceleration.

His feet started getting heavier. As he tried to keep his eyes open, a lightness spread over his body. He saw a vivid blink far ahead. It was a breach! It had to be. Everything else, Sonic included, seemed to filter into the back. He was getting closer and closer, his speed making the lightning heavier than normal. A gloved hand reached out…

Something had gone wrong. His feet were no longer on the ground. The world tumbled sideways and he felt himself flying off the ground. Suddenly, his eyes zeroed in the approaching sand and he let out a yell. After that, nothing was visible.

From far away, a worrisome cry sounded.

* * *

 **Another crazy ending. These may seem a big drastic, but they're supposed to make the stakes feel more real and dynamic. Anyways, all I can tease for next time is some progress on both ends, as well as for our up and coming baddie. You could say he's got some Metal in his sleeve...Adios, folks!**


	5. Parallels

**A/N: I'm back! Spam reviews, school, other projects, and balancing this all has been the main reasons as to why I've been away, but I am back! And I won't stop until this story is successfully completed! Thank you to all the support, friends! And speaking of support…**

 **Shian1998: Barry's situation is a lot more relative than the cliffhanger ending seems, but good that you're worrying! And thanks for the support, it's very helpful!**

 **MarvelousManiac: Good thing you caught onto that! All will be revealed in this chapter…**

 **Aragorn II Elessar: Thanks for the reviews!**

 **And special thanks to ales1698 for favoriting and following, means a lot!**

 **Back to the story! This is probably the longest chapter I've written for this story since the first one.**

* * *

Chapter Five

 _Parallels_

* * *

Lights. Pain numbing his arms and legs. Barry had just opened his eyes a smidge before a mix of shouting and heavy presences overloaded what he had for functioning senses. He raised a pain-bursting hand to make understanding of it all, only for something to grab onto it and push it back towards him.

"Don't move, okay? Let me figure this out."

"Tails, there's got be something you can do, right?"

"We'll see once the results come in, Sonic…until then…we've got to wait."

He blinked again and fell back into the void, almost in the same vein as sleep.

* * *

"Hey, buddy. How ya' feeling?"

He knew Sonic's voice all too well, opening his eyes. Contrary to what'd he'd expected, his body wasn't in a cast. His healing factor must've kicked in and done the work for them. But anyways, he was rather happier to know that he could move and function again. He sat up on the bed, surprisingly stable for his size, and looked at the hedgehog.

"Great," Barry surmised. He shook a hand and then the other, sensing nothing wrong. "I bet you're probably looking for some kind of explanation, right?"

Sonic's foot tapped impatiently in his spot. "Yep. How'd you heal so quick? And what exactly were you trying to do back in the desert?"

"I…when I was running back in the desert, I think I might've been unconsciously trying to get home."

"I don't follow," Sonic expressed.

"Sorry, I didn't explain," Barry replied. He got up off the bed and stood to walk a bit. "If I run fast sometimes, I can break barriers between dimensions at will. The first couple times I did it, it was by accident. It's like I'm running so fast into the Speed Force – the place where my power comes from – that history and the universe is my racetrack. I've gotten better at it, but when I tried it out there…something went wrong. It was like I was being stopped from entering it."

"Hmmm," Sonic mulled over. He put a finger to his nose in thought while looking at Barry. "I've felt that, too. When the universe feels like it's actively pushing against you. But this has to be different, right? Tails said the injuries you got weren't from the nosedive."

"Correct," Tails said as he walked in. The fox was wearing a lab coat and was holding some kind of folder with a handful of files packed into it. "While you look pretty healthy, Barry, I'm thinking I know what happened. Check these out." He put the folder on the closest file cabinet and procured two sheets of photos. Sonic and Barry looked them over, with what appeared to be two very different images of his cells. One was looking rather healthy; the other, however, was charred to the molecular level.

"Whoa…That's off," Barry managed to get out while processing the images.

Tails nodded. "These are your cells before and after. It's like when your body was filled up with your 'speed force', it was completely rejected and for a moment stopped working. Honestly, the situation seems one of a kind."

"Good thing for that accelerated healing of yours," a paled Sonic interjected. "You'd be toast without it."

Barry scratched his neck, confounded at this shocking piece of evidence. Had he really been the hurt? Were there any lingering side effects? Then he decided on a better question. "Doc, what's the diagnosis? You have an idea what caused this?"

A little aware of the attention he was getting, Tails folded his arms unsurely. "My best guess is that something made your body…corrupted."

"Huh?"

"I-I mean, you normally should've been able to cross dimensions at ease, like you just said. Somehow, getting here must've 'infected' your system with a chemical or energy that we can't detect." Tails linked his fingers nervously. "Whatever it was…is making it so you can't go back."

The features on Barry's face paled. "No…no, this can't be happening!"

"Hey!" Sonic put his arm on Barry's hip. "We're gonna' figure this out. We've got to keep it together until then, all right?

"But- "

"Flash." Sonic wasn't joking. "Let's just take a breather, okay?"

The next few seconds passed without any response from anyone in the trinity. Barry thought on what Sonic had pointed out. His head nodded.

"Okay."

"Great," replied Sonic. "Tails, can you keep looking at the results? We could probably take a walk and give you some time."

His furry friend nodded. "Understood. You guys get some air. I can handle the results enough as is."

Positive, Sonic gripped Barry's hand and led him out the door towards the city. The speedster snuck in a worrisome look before he went, and after the door closed, Tails felt something bubble in his stomach. Dark things were definitely at work.

But he didn't know how to fix them.

Yet.

* * *

Cisco and Gypsy escaped from their breach into the familiar hallway of S.T.A.R. Labs, landing with grace. The two easily collected themselves before walking towards the cortex; and given how dire the current situation, that made sense.

"What's up, people?" Cisco announced to the assembled team, hoping to spark up some humor with his words. "Found who I was looking for, in case any were doubting…"

"Gypsy." Iris walked closer, seeming to stand still before continuing on what she'd planned. "Hi."

"The same," the bounty hunter exchanged back, "though I understand why things are a bit gloomy around here." In an act of sudden empathy, Gypsy gripped Iris' hands with her own. "We're going to find your husband, Iris. I vow on my word."

The proclamation seemed to instill some hope into Iris, brightening up. "…Thank you." Then she snapped into boss mode. "About that…do you know anything that might help us find Barry?"

The collector smirked. "Yes. Can I use your whiteboard to explain?"

Harry coughed. "Be my guest."

"Thanks." She strolled over to the transparent whiteboard, popped a marker off and began drawing small dots across it in red marker.

"I told you when I first came here the reason my earth has Collectors was that we enforced strict no-travel between our planet and others. But that's not the whole reason."

Joe was surprised. "What else is there? You made the rules pretty clear when you were hunting H.R."

Gypsy's expression drooped. "I did, but my father entrusted me to keep this secret hidden forever. If it ever got out-"

"You can trust us," Caitlyn pleaded. "Considering how advanced your earth is to ours, who'd believe us?"

"Yeah," Ralph chimed in. "I've got a strict confidentially policy for my customers. Well, for the hot ones at least."

"On second thought, all of us except Dibny," Harry barked. "Continue, please." This earned him an annoyed look from Ralph.

Gypsy turned back to the board, concentrating when she started drawing a set of what amounted to seven identical emeralds. "What my father and his allies knew, long before I was around, was that there was an ancient wizard known only as Kaon. He was a magical demon who craved power and apparently put most of the energy he confiscated into seven emeralds of his design. Then he used them to instigate the Plastoids' aggression, inciting the war that instigated our ban on interdimensional travel. It was…madness…"

"Let me understand this…" Cisco processed, "…you guy's ban was started by this ancient wizard, who used seven powerful objects to cause a war. I never thought I'd say this, but…this is just like Lord of the Rings!"

"Cisco!" Iris cried out.

He swallowed. "Sorry, got off track. Better now."

Joe walked closer. "What about these Chaos Emeralds? Whatever happened to them?"

Gypsy returned to her stern look. "When my father and his allies took down Kaon – and I don't just mean defeated – a race known as the Echidna came from some point outside of our multiverse. They claimed to be the caretakers of similar emeralds and said they could keep them hidden. With no other options, my father gave them over. And ever since, we've never heard from them."

"You don't think…" Iris started, her mind locking in on something. "This place the Echidna came from…is it reachable?"

Gypsy put her hands up. "I don't know. Nobody has ever tried finding them, mainly since it would conflict with our earth's policies. The only person who's ever tried was my father, and that was once when he didn't trust them."

"Bit of a bind, then," Harry lamented. "Wonderful."

Iris looked out to the rest of the team "Any other ideas?"

Silence followed her suggestion, and she was almost prepared for running into the same roadblocks; then Cisco realized something. "I think- no, it's too- but…I don't- "

"Ramon," Harry barked. "If you have a suggestion, say it. Quickly."

He linked his hands nervously. "I couldn't find Barry from those particles…but that was because he's outside our Multiverse. And then Gypsy went and told her whole Tolkien story…so what if we BOTH vibed them?"

Shrugging, Gypsy walked closer to him. "Couldn't hurt. From the sounds of it, this team is out of options."

"Gotcha," Cisco agreed. "Yo, Ralph! Where're the particles at?"

"Why am I the one who – oh!" Ralph reached into his coat pocket and procured a thin tube of grainy manila sands. His arm elongated past the console table (and a mildly surprised Caitlyn) before reaching and holding it out to Gypsy. Disturbed by the display, she took it and his arm retracted to normal length.

"Sorry – what was that?" She asked.

"He does that a lot" Cisco summarized. "You'll get used to it."

She looked crossly to him. "Ciscy, I don't know if this is going to work…but I'm willing to try."

"Good mindset," Harry interrupted. "Theoretically, all you need to do is both vibe it at the same time."

"Nice pep talk, Harry," joked Cisco. When he caught Gypsy's glare, he coughed and went to hold onto the particles. She did the same. No change seemed to alter how they were acting, and Iris stiffened her grip on the console table in anxious waiting.

Suddenly, both vibers gasped. The action went on for quite a bit before they relaxed into normal breathing. Gypsy was at a loss for words and Cisco was trying to breathe normally again.

"What happened?" Iris worried. "What'd you guys see?"

The collector put a hand to her temple. "Things…I've never understood. It's like the multiverse just became a lot clearer."

"Tell me about it…yow," Cisco interjected. "I feel like Doctor Strange when he got trippy on magic LSD."

"But what did any of that do with this…'dimensions outside of' the multiverse?" Joe questioned.

"Sorry, lost track again." Cisco composed himself. "I think, scientifically speaking, we might've found a crack."

"A crack that could lead us to the dimension of the echidna," said Gypsy. "It's a risky one, though."

"Then let's take it." Iris said standing defiantly. "Let's find my husband."

* * *

"I did not imagine this place would be sunny!" Barry mentioned when he and Sonic walked down the city street, all while trying to block away the sun. "Not that it's bad, just…nevermind."

"You live in a city, right?" Sonic questioned. "Why'd you think Station Square wouldn't be?"

"I…It's like when you meet something in real life," elaborated the human speedster. "It's just a lot more…normal that you take it for. Like meeting you for instance."

"Thanks for the compliment," Sonic replied cheerfully. "How's your body feeling, by the way?"

He flipped his hands again casually. "Fine. I feel good. It's just those scans Tails showed me. They looked…morbid."

"Don't get your hopes twisted up about it. We've got this sunny day to enjoy. Maybe there's a chili dog stand around?"

Barry couldn't help chuckling…and thinking about Sonic. He was such a positive animal. He never seemed to lose his temper or focus as Barry had in the past. Maybe he hadn't seen that part of his personality yet, but if things got worse than they slightly were, he knew he could rely on him for help.

"SONIC!"

The hedgehog, out of nowhere, froze and turned – straight into a life-sucking hug. Barry blinked his eyes to properly perceive a pink hedgehog smothering Sonic with her arms and torso. She had severely shorter spikes and wore a red dress. The CSI gulped when he glanced down at her waist and saw a massive hammer tucked in there. _Why is that there?_ He thought. _Okay, more importantly – who is this?_

"I told you I'd catch you, Sonic! And now you're here!" The hedgehog fired off as she squeezed the life out of him. Barry fought to make himself not cringe at the sight, or even when he heard what he thought to be "Save me" from the blur.

"…Amy?" The overwhelmed hero managed to get out. "…You're… crushing… me."

"Ohhhh, sorry!" No sooner had she let him go than he breathed hurriedly to recapture his air. She astutely picked up on the lankly human standing above them. "Hi! Who're you?"

"Barry Allen," he replied briskly, shaking his hand with her gloved one. "Sonic's been…giving me a tour, considering I'm from out of town?" He rubbed the back of neck nervously but managed to keep his cool intact. "Amy" didn't seem to pick apart the differences.

"Is that so? Good for you!" She spat back. "I thought that Sonic was going to let me chase him today, though."

"Come on, Amy," Sonic pleaded. "Can't I at least have one day where I'm not being hounded by you?"

"In your dreams, mister!" she declared. "If you've got any more actually warrantable excuses, then spit them out now, or you're going to meet my hammer!" She fingered the edge of the mallet tucked in her belt warningly, and both Sonic and Barry's eyes' bulged. The hedgehog sweated; realistically, he had no escape from Amy, because running from her would only result in more chasing. Unless…

He looked down the street, and quickly noticed the one thing Amy's will was weak to; buttermilk cupcakes sold out of a food truck.

"Hey, look at that!" He exclaimed. "Buttermilk cupcakes!"

Her eyes bulged and she turned, immediately fawning. "What? Hey, stop right there! Sir!" The pink fangirl having left, Sonic grabbed Barry's arm and sped a few feet into a hidden alley.

"Who was that?" Barry asked. "Are you and her a - you know – "

"No!" Sonic refuted. "She's just this hedgehog with a short temper and a big mallet…and a massive crush on me! She never stops chasing me! She's convinced we're forever destined to be together."

"And you're not, even though she constantly sticks by her opinion on it?"

"Yeah…how- "

"I've had a couple experiences on stuff like that. Sometimes it's true, and others…not so much," pointed out Barry. He glanced back to the alley. "But…who knows? Maybe she'll figure it out later on."

"I hope so," Sonic conceded. "Where do you want to go next? There's the park, the stadium, the harbor…Lots of options."

"Hmmm…"

The CSI froze. His ears perked and he turned back to the street they'd been on. Cautiously he ran forwards, Sonic suspicious and on his tail. When he returned to the street, the duo heard a massive amount of panicky noises from the distance. The formerly peaceful scene had devolved into a frenzy.

"That doesn't look good," Sonic bluntly stated. "How fast can you- "

A whish answered his claim, and when he turned, Barry was dressed in his Flash suit. "Pretty fast."

"Thanks. I like to keep a bag nearby for this kind of thing." His glare focused back to the frantic noises in the far distance. "What's up there?"

"The heart of the city. Shops, businesses…You want to take whatever this thing is together?"

"You bet." Barry smiled as he fitted the mask on, took his runners stance, and let the lightning shoot him forward. In the flurry of chaos, he arrived at a slowed-down version of the area. True to Sonic's words, it was an open area filled with people and businesses. He quickly picked up on something dashing its' way across the area…

As a blue light.

"Sonic?" He was so confused he let time scram back to normal and was quite unprepared when said blue blur crashed him into a nearby newspaper stack. He massaged his head and looked towards what he thought was his friend.

But he was dead wrong.

It wasn't Sonic, rather some kind of artificial replica with metallic skin and a cold glare backed up by deathless red eyes. The hedgehog's trademark gloves were replaced with sharp grey claws. Even its' legs were longer than his.

" _Subject appears to be disoriented,"_ it breathed. Since when was he a subject? " _Orders to capture will be followed."_ Its right claw dashed for the Flash, but he luckily managed to phase as it dove through where his heart would've been. Reappearing behind it, he winced when it swerved around with no real effort.

"What are you, some kind of clone?" He blurted.

"More like a bad rip-off." Sonic had finally arrived next to him, looking dead serious. "This guy's Metal Sonic. Eggman made him – though he missed a few key ingredients."

" _Metal Sonic is superior to Sonic,"_ the robot wheezed. Its claws tensed while it began circling the two. " _It will prove so by capturing you and the anomaly."_

Anomaly? It had to be referring to him. "I'm better than an anomaly, pal. I'm the Flash." He breather heavier than he had in a long while, dashing forwards. Sonic was right beside him and as the two locked fists with Metal Sonic, a powerful light flooded the area.

* * *

 **A/N: Plot progression! Yay! Both Barry and Sonic and Team Flash are getting somewhere, but we all know a certain doctor isn't going to let that happen. Next chapter will definitely reveal stuff regarding that, so get excited! Adios til a week from now, folks!**


	6. Uncertainty on the Rise

**A/N: Happy post-Thanksgiving everyone! It's been a pleasure to do this story, and this new chapter should move things along quite (no pun intended) fast. Though considering how "Elseworlds" just wrapped up and announced "Crisis on Infinite Earths," there's a lot to catch up on. And believe me, I will, just at a much slower pace thanks to school work.**

 **Shian1998: Thanks! I understand your POV on Amy, but for me, she's more of a hybrid fangirl. She pines after and does kind of annoy Sonic, but also tends to figure out when she does that and can be a badass you can rely on. She will get better here, trust me.**

 **Aragorn II Elessar: Thanks! Lord of the Rings tends to be a great fantasy break whenever it's mentioned.**

 **Apologies if this chapter feels short or rushed. Just really want to get this story moving again from both sides.**

* * *

Chapter Six

 _Uncertainty on the Rise_

* * *

Ralph wasn't one for exploring S.T.A.R. Labs that much. There were times he thought he'd get lost in the building's bowels and then have to embarrassingly explain it to his co-workers in Team Flash. Seemed too much of a stretch, he thought, not minding the pun in there.

But given what he was looking at right now, he realized maybe he should've considered that before.

Cisco called it their "inter-dimensional portal." Some kind of breach (he still could barely wrap his head about how Cisco's powers worked) machine that could help them find Rookie. The room it was located in was quite large and has several monitor consoles hooked up in the sides. Harry had claimed that it sent them to parallel earths and back in the past multiple times.

Would it do so now?

"You guys ready?" Caitlyn asked Cisco and Gypsy. The duo was located in front of the spot, preparing for the insane effort they were about to try to pull off. "This might be intense…I mean, more than usual."

"Intense is a Tuesday for me," Gypsy chuckled. "We knew what we were getting into."

"Totally," Cisco chimed in after his girlfriend. "Ready when you're all ready….Did I just repeat ready twice?"

"Yes," Harry chirped unenthusiastically. Joe and Iris stood next to him on the steps, nervous. She clutched at her heart; all that she was focused on was finding Barry…and bringing him home.

"Cisco, Caitlyn, Gypsy…"

"And Ralph!"

Iris sighed. "And Ralph. I trust you. For the team, for what matters…bring him back."

"You know we won't come back without him," Caitlyn said.

"Neato," joked Cisco. He gulped, flipped his Vibe goggles on, and then breathed in. "Guess that means we're ready for this?"

Gypsy nodded, and the two aimed their hands at the machine. Their fingers and faces strained for what looked to be half a minute before a thin crack rippled right in front of the spot. Their trademark blue and red energy propelled from their hands and hit the rip, applying more and more until it lost its will and widened into a glowing purple breach. They collapsed to the floor, breathing heavier.

"You two all right?" asked Ralph.

"…Think so," Cisco breathed out shakily. "That…took a lot out of me."

"Save it for the trip, Ciscy," Killer Frost joined in, her icy hair freezing over Caitlyn's own. She noticed Gypsy's dark glance at her. "What?"

"Only I call him that."

"Sorry…I'll keep that in mind."

Ralph fought hard to suppress a laugh and turned back to the breach. "Uh….is this safe?"

"Excuse me? Who do you think made this?" Cisco huffed and pointed a crossed finger at him. "We're this far already, Ralph! Just go with it!"

"But-"

"You heard him," said Gypsy as she gripped his arm and then darted into the portal. "Time to bolt!"

"Hey!"

Cisco turned back to Frost and the others. "I just got the sinking feeling that he's going to pay one of us back for that."

"Wouldn't be surprised," she blasted off. "Hurry it up, slowpoke!"

"…Pokémon references? It's on!" He sent one last look back to the support team and then followed Frost into the purple breach, disappearing before it blinked out of existence.

Joe coughed. "You think they're going to be okay?"

"If they're just as determined as they normally are," Harry snorted, "then yes. The thing we have to worry about is whether they'll be able to get back…from wherever they went."

Iris turned to him. "They will."

The lightning inside of her knew they would.

* * *

 _This is insane!_

The thought was followed by something heavy making its way up to Sonic. He moved just to feel it lightly graze his cheek, and that was before the twisting of metal pummeled into his back. His body shot forwards towards a residential building. Breathing quickly, his feet buckled on the glass and he luckily moved onto the sidewalk, not hurt too much.

The hedgehog's green eyes looked around. The small open square they'd been fighting in looked to be free of onlookers. The bad news? Cars and small newsstands had been either devastated or fallen in a worse condition due to the conflict. At the very least, he wanted to end this quickly.

But Metal wouldn't care as much.

"Right…" he mused, swirling around to see the metallic doppelganger mere feet from him. "This another rematch? Because we both know the original always beats copycats."

" _Metal Sonic superior,"_ it repeated unsurprisingly. _"No, this time on orders."_

And then his claw shot forwards. Sonic dodged it, but the sweat flew from his face to greet it.

 _He really is getting faster._

He took off again, dashing onto the side of the buildings and circling around as best he could. Metal was just…standing there? Why? No, he had to be planning something. He wasn't this dumb.

"Seeing double?" He glanced to the Flash, already running alongside him as they circled for another loop. "Had a couple of those myself!"

Sonic let out a hard laugh as the wind bit into his face. "And what's your solution?"

"Take them down with all you've got."

"Not a bad policy!" Feeling better now, he swung back. "Want to take him together?"

"I've got an idea," the scarlet speedster shouted, "but I need you to lead him away from here – and then back!"

"So just more running?"

The Flash shot him an annoyed look. "Either that, or we just get tired!"

"All right, Romeo!" Sonic blasted off to the middle of the square and managed to get out his exclamation right as he passed the doppelganger. "Catch me if you can, Mets!"

Its red eyes enlarged, its claws glistening. A single pop from its' turbine sent it right after Sonic, interweaving through the tops of the buildings and such. The speed picked up but the blue lines of good and evil seemed to be just as fast as ever.

And that was what Barry had hoped for. Parked on the top of a nearby tower, he could see the hedgehogs running in his direction. His palm sweaty, his focused his will and then charged the lighting into the tips of his fingers. The electricity soared off to them.

Just as he had planned.

"Now!" He shouted. Thankfully, Sonic had heard the comment; Right before the lightning hit him, he fell off the building to safety. Unfortunately for Metal Sonic, he hadn't seen it coming and could only look up before the impact came.

BOOM!

Shielding his eyes for a moment, Barry looked about. But all he saw a smoking crater on the side of the building.

So where was Metal? Kaput?

"Don't see him either, huh?" Sonic asked once he'd dashed next to him. "Not the first time he's pulled the disappearing trick."

"He was pretty tough, but still…" Barry knelled down and focused on the crater, even when nothing changed in his vision. "This Eggman built him?"

"More like copied him from me."

"Where do-" He paused.

Something was coming.

It hit before he could finish the sentence. The gut punch sent him back, Sonic crashing to the ground. All that he saw was a blue claw.

" _Superior."_

Then the light seemed to burn into white.

…

"Uhhhh…"

"…You….got the…number on that….robot?" Was that Sonic?

Suddenly, another voice took center stage. "Ah! The two of you are awake. Perfect! Time to wake up and face me, please."

They looked up, clearly in a dome-shaped lab draped in shadows and malicious green light. On a balcony, hundreds of feet above them was a rotund man in a red-and-yellow jacket. A surprisingly long and brown mustache obscured part of his face, complete with cartoonish goggles, white gloves, and tweed legs draped in black.

"Eggman," Barry breathed. It had to be him, what with Sonic's articulate description and monologues. He'd get him, that-

Apparently not, for when he tried, all he did was slam into an invisible barrier and bounce back into the ground. He grimaced while holding his check.

"Forcefield," the madman gleefully revealed. "Helps to keep varmints like you contained. Now, I'm sure you would like to know _what_ you're doing here?"

"Yes," they answered.

* * *

"Whew!" A feeling of warmth flooded over Cisco when he saw colors merge into reality again. The ground came next, sending him nearly tumbling into the other three. Wearing off the disorientation, he looked around to see – a city. The sign " _Station Square"_ popped instantly.

"Okay…" Ralph chortled off, dumbstruck at the sight. "So we're on another world?"

"Obviously," Frost pointed out. "Do you need a big red sign to spell it out?"

"Actually…I think there already is one," said Gypsy. "Look."

That was when the four noticed they were surrounded by everyday people.

And animals.

"Starting to get the idea we jumped into a Disney cartoon," Cisco hysterically commented. "Directions, anyone?"

"Your guess is as good as mine's." Ralph positioned. "Shouldn't there be a cop precinct somewhere around here?"

"Probably," Gypsy surmised. "For-"

Out of nowhere, some black-and-red dash blasted into the four of them. Cisco and Gypsy fell over, Frost twisted into a wall, and Ralph crumpled in over himself. Just as they were coming to, Cisco looked to see a gun pointed directly in his face.

"Associates of Eggman?" The individual guessed out loud.

His eyes went back to look over the figure, causing his mouth to drop in shock. It was an animal; a hedgehog with black and white fur, red stripes, and darkened eyes gazing directly at him.

 _A talking hedgehog with a gun? No. Way._

"Who in the what now?"

* * *

 **A/N: More new characters! I think that Metal and our new friend are probably, but maybe not, going to be the last couple Sonic characters so the cast isn't so big. Anyways, thanks to everyone's who's read this and continues to read. Really means a lot! And I will get back on the regular schedule, so thanks! Till next time.**


	7. Egg-Celent!

**A/N: Happy new year! Thanks for the reviews, folks! Happy to have helped you all with this story. I'm in a better place and I'm very excited to keep chugging at this one. Trust me, BIG things happen this chapter. Special thanks to jjb0420, inukaiser, and DiamondShines for following and favoriting. Now onto reviews…**

 **Shian1998: Thanks!**

 **Marvelous Manic: Thanks for the compliment!**

 **Fleetlord Avatar: Thanks! Things are about to get a lot more intense.**

 **Aragorn II Elessar: Quite right, but you never know…**

 **Inukaiser: Thank you. Knuckles already was in some earlier chapters and will return shortly. Rouge…maybe…**

 **Now, back to the story!**

* * *

Chapter Seven

 _Egg-Celent!_

* * *

Eggman's mustache twitched as his gazed at his captives. "My, what a sight the two of you are! At least my hypothesis that Sonic couldn't be the only speedster is now proven true!"

"What?" chuckled Sonic. "Since when?"

"Since you destroyed every one of my schemes, you blue rat!" His face vented a surprising amount of cartoonish anger, to which he eventually relaxed.

 _Reminds me of Tokamak,_ Barry observed reminiscently. _If he was an evil genius not given radioactive powers…_

"But I lost track, apparently." The villain strolled to the edge of the railing with his hands mischievously interlocked. "Now… What do I call you?"

"It's the Flash," Barry proudly declared.

"Mmmmh…" the evil genius mused. "Catchy name, befitting your suit. Funny how I've never heard of you…"

Barry gulped, looking to Sonic. Normally, he'd prefer to blab about how he came from another dimension and that there was a greater multiverse. But in this situation, he felt spilling the beans to this Eggman would create more problems. Was it really wise to tell an obvious evil genius about other worlds?

The blue hedgehog seemed to catch his drift and coughed. "Yeah. Funny how that happens." Desperate to change the topic, he then remembered Metal's presence. "And speaking of that, I saw you got Metal ready for our next race."

"Your next race? Bah!" Eggman gaffed. "He – I mean, my creation beat you this time! Your pathetic speed was no match for his improved circuits!"

"He does this much?" asked a growingly bored Flash.

Sonic's eyebrows lowered in confirmation. "Yep."

"Do not ignore me!" Eggman yelled at them. "I have you miscreants now, and there's nothing you can do to stop what I have planned!"

"World domination?" Sonic asked mockingly.

"Better." He pressed a small button on the railing that caused it to slowly lower towards them. The action started giving Barry the feeling that something was amiss. What a true thought, as Eggman's hands came together in a teasing manner. "You wouldn't believe what happened when, oh, I don't know, FOUND THIS." He reached behind himself and pulled out –

The Chaos Emerald.

Sonic froze. It was the same one that he had been missing.

"Makes quite the difference, does it now?" teased Eggman. He was just enjoying the emotional distress permeating out of Sonic. "This appeared in my laboratory just a few hours ago, bathed in some kind of energy. Almost as if it was…out of this world. More precisely, this universe."

"Oh no…" Barry mouthed. _That means Tails doesn't have it anymore!_

"Oh yes," Eggman responded in a gleeful mood. "Before, I was only concerned with conquering the world as it was. But now? There are other worlds out there, and I would just love to find them!"

"So that's how you amped Metal," realized Sonic. "Gave him some of that emerald's juice, didn't you?"

"Precisely," Eggman replied.

Barry marched to the edge of the force field determinedly. "You think you can hold us? Fine. Be like that. But we will get out of here! And you're not going to get away with something this horrible!"

"Oh, my dear Flash…" he clicked a finger onto his left wrist. Suddenly, a slight hole opened up in the floor and started enveloping them. "You think that you are in control of this situation? Not so. But don't count yourself out quite yet, for there is something about your power that fascinates me."

They scowled, but captive as they were in the force field, they could only grimace as their bubble was swallowed into darkness.

* * *

"Who. Are. You?"

Cisco's whole body was frozen. He couldn't decide whether it was being in a new dimension that was making him wet his emotional pants, or if it was the talking black hedgehog with a gun locked on his face. Both choices bordered on the edge of weird. This type of weird was enough to make the term meaningless.

"…Cisco Ramon?"

Ralph snorted from a couple inches away. "Dude, what happened to revealing our secret identities?"

"Oh, I'm sorry," Cisco yelled to him while turning, "are you the one with a gun on you? Half the people in Central City know who the Flash is, Ralph!"

Gypsy groaned. "I don't think your squabbling is helping."

"You don't say!" Cisco fired back, then looked right back to the gun. "Hi…what do I call you?"

The hedgehog's eyes locked in silence at him. "Shadow." His fist tightened into what Cisco swore was a temporarily green-lit hand.

"Okay…uh, we just kind of woke up from a really long nap?"

Shadow looked back to the destruction. "I don't believe you. You're all too oddly dressed to be sleeping out in broad daylight."

"Then maybe you shouldn't point a gun at us!" Ralph rattled off. "What?" he asked when Cisco gave him daggered eyes.

The hedgehog shook his head, annoyed. "I'm taking you in for questioning."

Gypsy started to get up, her hands on the verge of glowing with breach energy. "I happen to be a fellow law enforcement agent, but last time I checked, we had a thing called due process."

"Not for when Eggman is involved." The gun in his hand clicked and twirled.

"Wait!"

The group looked back to the entrance of the space, confused by the intrusion of a pink hedgehog with a hammer in her left palm. Cisco's eyebrows scrunched as she got closer. How many more colorful animals were there on this earth?

"Rose?" Shadow demanded. "What are you doing here?"

"Shadow!" She came to a stop and caught her breath, her hand paused. "There was…big scuffle…Metal Sonic…captured them…"

"Captured who?" Shadow's brows perked.

"…Sonic…and some red guy…" Then she fell to her knees.

Intrigued, Cisco got up. "Some red guy? Did he have a mask on? Yellow lightning on his costume?"

Amy nodded. "Yep! You know him?"

"That sounds like the Flash," Frost pointed out obviously.

"Who wouldn't think it'd be him?" Ralph interjected. He looked to Shadow. "No offense, but we're looking for our bud, and pinkie here seems to have seen him. So…"

"Hold it!" Cisco yelled, grabbing everybody's attention. He pointed to his cellphone, a red dot blinking in and off on the pixelated screen. "I got something!"

* * *

"Grraaagghhhhh!"

Once again, Barry was pummeled back by the cyan light of the force field. Sonic lay on his back and gave him an empathetic glance. "Not working?"

"No, it's not!" Barry blasted off, collecting himself. "Phasing's not working, running in a circle isn't doing a dent…we're trapped!"

"Obvious, huh?"

Barry whirled around frantically. "How can you be just laying there? We have to get out of here!"

Sonic's eyes closed, and then…he laughed. The other speedster was a bit taken aback at the action. "Flash…you're too riled up by this. I've been held captive by Eggman plenty of times, and rushing and thrashing didn't do much for me." He looked in his direction. "You want to know what helped?"

"What?"

"Lying down and...just thinking. Here, take a seat." Sonic patted the ground with his gloved hand. No better options present, Barry inclined to do so and begrudgingly laid back close to his friend.

"Now what? Is this supposed to scare Eggman?" He asked.

Sonic snorted. "Nope. But…it does give some perspective."

"On what?"

"Think. We're in a bubble. Eggman thinks he has us. What can you do that he doesn't know about?" Sonic's head twisted to give Barry a hard stare. "What can YOU do that'll help us?"

So Barry thought. He fell back into the collective synapses of the last few years and everything he learned as the Flash. Friends made, people lost, enemies that rose and fell across masses of weeks. Once or twice he happened upon a memory of "Wells" or "Jay," but brushed those aside because-

 _Wait_ , he thought. _Last time I saw Jay, I- oh. That's it!_

"That's it."

Sonic looked up hopefully. "You figured it out?"

"I did," Barry exclaimed. He got up and extended an arm. "Eggman doesn't know about Flashtime, and I'm pretty sure I can use that to our advantage." He noticed Sonic's confused look and sighed. "It's when I vibrate so fast that time slows around me."

Sonic was taken aback. "You can do that?"

"You bet," said Barry coyly. "And, I can make it so others can do that as well."

Gleeful, the hedgehog took his hand. "Consider me up for it. Whatever you've got going for us."

Barry blinked, put his hood on again, and let the speed flow into his blood. The pressure went into his head but then exploded around him, and after opening his eyes, found the force field to have frozen into a single cyan sheet of color. He looked to Sonic, who seems remarkably the same despite the crimson and yellow wisps circulating around them.

"Are we-" Sonic began to ask.

"In Flashtime, yes. Don't let go, okay?" Barry walked closer to the barrier, tightening his arm and aiming it at the currents. "I don't know what's going to happen when I try this, but…just hold tight." With the hedgehog's trusting eyes locked on him, he let his hand vibrate and then thrust it into the force field.

The next thing either of them saw was an overload of cyan and the feeling that time was speeding to catch up with them.

* * *

"I brought this meta tracker on my phone," Cisco explained hurriedly. "And considering the spike of tachyon particles I just found on the GPS, Barry's definitely nearby."

"Then what are we waiting for?" demanded Frost. Her hands froze over in excitement.

"Hold on," Amy said. "I'm coming with you!"

Gypsy looked confused. "Why, exactly?"

"Because your friend and Sonic got kidnapped by Eggman!" she exclaimed profoundly. "Sonic needs my help, so I want to pitch in."

"Right," Ralph thought out loud. "You and your hammer…Also, who exactly is this Sonic?"

Amy chuckled, gripping her piko piko hammer in her other hand as she did so. "He's a hedgehog that's fast…real fast."

 _So just like Barry,_ Cisco mentally noted. _Got ya._

"Count me in as well," added Shadow in a dark statement. "I still have a warrant for Eggman's arrest."

Cisco lowered his eyebrows. "Uh, weren't you trying to arrest us like a minute ago?"

"That was when I assumed you worked for the maniac," Shadow replied. He flipped his gun into his side holder and then tightened his fists. "I have a tip as to where Eggman's current base might be. Any better idea beyond rescuing the faker?"

"Works for me," Gypsy said. She looked to the other Earth-1 heroes, finding a sense of general agreement, then turned back to him. "What's your plan?"

Wincing, Shadow gripped into his quills and pulled out a crystalline object. Another chaos emerald appeared there, this one ruby red. Before the awe-stricken Team Flash could question how he'd gotten his hands on one, his eyes inflamed with power as he uttered two words.

"Chaos Control!"

Green spirals of energy swerved around the team and encircled their space, hummed, and then entrapped them. They had teleported, all thanks to a chaos emerald.


End file.
